Apparatus for driving electric car by inverter-controlled motor through gear mechanism

An apparatus for driving and controlling a car, comprising:

• a large gear directly connected to a wheel shaft;
• small gears meshing with the large gear;
• AC motors connected to the small gears, respectively;
• inverters connected to the AC motors, respectively, for supplying power thereto, DC input sides of the inverters being connected in series in multiple stages to a DC power source of high-voltage so as to divide a voltage of the DC power source into a standard voltage for each of the inverters;
• and
• an inverter controller provided for each of the inverters, for calculating an output effective power value according to an input DC voltage value and an input DC current value both detected at the inverter, calculating an effective power command value according to a motor angular frequency and a torque command value, calculating a difference between the output effective power value and the effective power command value, and correcting the torque command value according to the difference.

An apparatus for driving and controlling a car, comprising:

• a single large gear directly connected to a wheel shaft;
• a single small gear meshing with the large gear;
• a single 3-by-n phase AC motor wherein n is an integer equal to or larger than 2, connected to the small gear;
• n inverters for supplying power to the AC motor, DC input sides of the inverters being connected in series in n stages to a high-voltager DC power source;
• and
• an inverter controller provided for each of the inverters, for receiving a DC source voltage value detected at the DC power-source and an input voltage value detected at the inverter, finding a difference between the input voltage value and a quotient obtained by dividing the DC source voltage value by n, and correcting an output torque command for the inverter according to the difference.